Clutch friction facing



Nov. 24, 1931.

L. v. CRAM CLUTCH FRICTION FACING Filed March 19, 1930 Patented Nov. 24, 193i UNITED STATES PATENT OFFICE my v. cm, or nnmorr, mcamm, Assreuon me am Morons conroam now. or nnraom MICHIGAN, A. conronanon or nmwm CLUTCH FRICTION FACING Application filed larch 19, 1980. Serial ll'o. 488,989.-

made with flat sides and-have been secured to the clutch plate by means of rivets. The

heads of the rlvets have been countersunk in the ring to permit proper frictional contact by the clutch plates and after a period of time, the ring wore down to the level of the rivet heads when it was necessary to replace it to secure p'ro er action of the clutch. This left about one alf of the clutch ring which could not be used and which resulted in a direct waste of half of the moulded ring material. In an effort to reduce the cost of the clutch ring, consideration was iven to decreasing the diameter or the thic ness ofthe ring but it was found that if the diameter be decreased, the acting surface of the clutch was decreased and interfered with its eflicient operation. There was no advantage gained by decreasing the thickness for the reason that the rivets demanded a certain thickness of clutch facing in order to hold the facing to the late. If a thinner facing was therefore use it would only result in the facing wearing out all the faster with no saving in material.

In considering ways of reducing the spinningweight of the clutch as well as decreasface of the rin ing the cost and eliminating the waste when the facing was worn down to the level of the rivet heads, the thought occurred that if the ad acent the clutch plate could be recesse or hollowed out or provided with a number of inwardly extending projections, that the same clutch action would be secured by the same thickness of moulded rin but with a lesser amount of material an a corresponding decrease 1n weight and cost. In forming the recesses or depressions in the clutch ring, it was found expedient to 'place them at intervals between the rivets for the reason that recesses could not be applied at the rivets because the material was weakened too much. If each recessed or indented portion were comprised of a single recess or depression, there would be a tendency for the clutch facing to spring or to move away from its adjacent friction surface. It was, therefore, found more desirable to form each recessed portion of a plurality of smaller spaced recesses leaving a plurality of ribs abutting directly a ainst the clutcli facing.

On the rawings: I

Figure 1 is a sectional view of a clutch shown in its housing.

Figure 2 is an enlarged fragmentary face view of a portion of a novel clutch ring. Figure 3v is a section on the line 33 of Fifiure'2.

eferring to the drawings, the numeral 2 indicates a clutch housin of any suitable type. The drive shaft. is indicated at 4 and t e driven shaft at 6. Secured to the drive shaft 4 by means of bolts and nuts 8, is one member 10 of the clutch'12. The member 10 is also the flywheel havinghthe starting gear 13 and is dished or has t e annular rib 14 to which there is secured by means of the machine bolts 16, the rear cover or closure 18. Mounted in the dished portion of the clutch member 10 is the second clutch member or ring 20 pressed away from the closure plate 18 by means of the coil springs 22, onl one of which is shown. A slidable sleeve is s own at 24 whichis adapted to be moved and strike against the ends of the levers 26 pivoted at 28 between airs of ears 30 which extend inwardly o the plate 18. Only one lever 26 is shown but as many as are desired may be used. The opposite ends 32 of levers 26 extend under plates 34 secured to the second member 20 of the clutch by means of the machine bolts 36. As the member 24 is moved inwardly,.it will swing the levers 26 on their pivots to cause the clutch member 20 to move away from the clutch member 10. The parts so far described are conventional and per se form no part of the invention.

spondin openings in the clutch plate. The heads 0 the rivets are set well down into the openings and leave about half of the thickness of the clutch facing extending beyond the rivet heads. 7,

: Inv order to make a lighter clutch facing to reduce the'spinning weight and also to reduce the cost of the moulded clutch ring, there has been provided on the side of. the clutch facing adjacent the clutch late, a plurality of spaced recessed portlons '46 which are separated by non-recessed portions 48 in which non-recessed portions 48 the rivets are received. 7

By referring to Figures 2 and 3, it will be noted that each recessed portion 46 comprises a plurality of smaller recesses 50 leav ing a plurality of ribs 52 extending transversely and longitudinally of the clutch ring. The reason for the plurality of smaller recesses or indentations 50 instead of one large recess is to prevent a sagging or springing movement in the clutch facing when the clutch is applied. If but one lar recess were made, the middle portion 0 the recessed portion would tend to push inwardly toward the plate when the clutch is applied and decrease the efiiciencv of'the clutch. The

- plurality of supporting ribs" 52 between the smaller recesses 50 will effectively prevent anyspring or sag in the clutch facing.

I claim: v

1. In a clutch, a clutch plate, a moulded clutch ring secured to said plate, said ring having a plurality of recesses on its face adjacent the plate. Y 2. In a clutch, a clutch plate a moulded clutch ring secured to said plate by means of rivets passing through said plate and ring, said ring having between said rivets a plurality of sections each comprising a plurality of recesses.

3. In a clutch, a clutch plate, a moulded clutch ring secured to said late by means of rivets passing through sai late and ring, said ring having between said rivets and on its face adjacent the plate a plurality of sections each comprising a plurality of recesses.

4. In a clutch, a clutch plate, a moulded clutch ring secured to said plate, said rin having spaced recessed portions, each of sai recessed portions comprising a plurality of smaller recesses.

5. In a clutch, a clutch plate, a moulded clutch ring secured to said plate by means of rivets, said ring having a plurality of recessed portions between said rivets and on its face adjacent the plate, said portions comprising a plurality of smaller recesses.

spaced recessed portions separated by min 7 6. An'article of manufacture, comprising a moulded clutch ring having a plurality of recessed portions, each portion comprising a plurality of smaller recesses.

. An article of manufacture, comprising a moulded clutch ring having a plurality of 

